Based on the experiments done by Beijing Labour Hygiene Institute, furhter research on the dietary value of rubber seed oil was made from 1975 to 1976. 258 rats and 125 mice were divided in to two groups fed on the diet containing 10;and 20;rubber seed oil respectively, while the control group was fed on a diet containing 10;or 20;peanut oil. The results can be summerized as follows: The nutritive value of rubber seed oil was slightly higher than that of peanut oil. The feeding on the diet containing 10;or 20;rubber seed oil for a long time showed no harmful effects on growth, propagation, liver function, serum protein, serum lipid, serum calcium and morphological changes of liver, kidney, heart, lungs, digestive tube, etc. The cytogenetic observations showed that there were no latent genetic adverse effects. The feeding on 10;or 20;rubber seed oil would cause a decrease in the concentration of serum lipids. It is conclude that rubber seed oil is a new source of dietary oil.